Absolutely lovely :)
1920s nightgown or lounging dress of pale purple cotton voile.
Trimmed with white valencienne lace. 
Colorful floral cotton floss embroidery at chest, hem and around ribbon ties at back.
Original purple silk ribbon tie at drop waist.
Scalloped hem.
Handful of small spots at front left.
Measurements:
Chest: 40" 
Hip: 52"
Length from top of shoulder: 51"